Create Octapad Using Arduino UNO Board
Updated: Sep 9, 2021
Things you need
1.Arduino UNO Board
2.Piezo Sensors
3.1M ohm Resistors
4.5.1V Zenar Diode
5.Jumping Wires(male to male)
6.Bread Board
7.Dot Board
softwears you need to build octapad
1.FL studio
Download using this link
2.LoopMIDI
Download using this link
3.Hairless MIDI Serial
Download using this link
4.Arduino IDE
Download using this link
Arduino Code
#define LED 02
#define PIEZ_CNT 8
#define DRUM_CHANEL 8
#define ANOTHER_MUTE_PIN_
#define SHOW_
#define CRASH 0
// #define CRASHC 54
#define PIN_CRASH_STOP 9
#define OPEN_HAT 90
//#define OPENING_HAT 200
#define KANAL_HAT 1
#define KNOPKA_HAT 100
int kick_treshold[PIEZ_CNT]={200,200,200,200,200,600,200,200};
long kick_mute_time[PIEZ_CNT]={60000,50000,50000,50000,50000,50000,50000,50000};
byte kick_note[PIEZ_CNT]={10,20,30,40,50,60,70,80};
bool mute[PIEZ_CNT]={1,1,1,1,1,1,1,1};
const uint8_t kick_pin[PIEZ_CNT]={A0,A1,A2,A3,A4,A5,A6,A7};
#ifdef ANOTHER_MUTE_PIN
const uint8_t stop_pin[PIEZ_CNT]={A0,A1,A2,A3,A4,A5,A6,A7};
int kick_val[PIEZ_CNT];
int velocity;
uint32_t tm[PIEZ_CNT], tm_led;
byte cnt=0, piez_idx=0;
void noteOn(int chan, int note, int velocity) {
Serial.write( (0x90 | chan) );
Serial.write(note);
Serial.write(velocity);
}
void noteOff(int chan, int note, int velocity) {
Serial.write( (0x80 | chan) );
Serial.write(note);
Serial.write(velocity);
}
void setup() {
Serial.begin(115200);
//Serial.begin(31250);
pinMode(LED, OUTPUT);
pinMode(PIN_CRASH_STOP, INPUT);
pinMode(KNOPKA_HAT, INPUT);
digitalWrite(LED, LOW);
for (byte i=0; i<PIEZ_CNT; i++) {
digitalWrite(kick_pin[i], LOW);
pinMode(kick_pin[i], INPUT);
#ifdef ANOTHER_MUTE_PIN
digitalWrite(stop_pin[i], LOW);
pinMode(stop_pin[i], INPUT);
}
ADCSRA |= (1 << ADPS2);
ADCSRA &= ~ ((1 << ADPS1) | (1 << ADPS0));
}
void loop(){
if (mute[CRASH] == false) {
if (digitalRead[PIN_CRASH_STOP] == LOW) {
noteOn (DRUM_CHANEL,kick_note[CRASH],0);
//noteOn (DRUM_CHANEL,kick_note[CRASHC],127);
}
}
if(piez_idx>0) piez_idx--; else piez_idx=PIEZ_CNT-1;
int adc = analogRead(kick_pin[piez_idx]);
if (adc > kick_treshold[piez_idx]) {
if ( tm[piez_idx] == 0 ){
tm[piez_idx] = micros() + 2000;
kick_val[piez_idx] = 0;
digitalWrite(LED, HIGH);
tm_led = millis()+10;
}
}
if (tm_led > 0) {
if (millis() > tm_led) {
tm_led = 0;
digitalWrite(LED, LOW);
}
}
if ( tm[piez_idx] > 0 ) {
if ( micros() > tm[piez_idx] ) {
if ( mute[piez_idx] ) {
mute[piez_idx] = false;
velocity = 127;
if (velocity > 127) velocity = 127;
if (piez_idx == KANAL_HAT){
if (digitalRead(KNOPKA_HAT) == LOW ){
//
}
else {
noteOn(DRUM_CHANEL,kick_note[piez_idx],velocity);
}
}
else {
noteOn(DRUM_CHANEL, kick_note[piez_idx], velocity);
}
tm[piez_idx] += kick_mute_time[piez_idx];
#ifdef ANOTHER_MUTE_PIN
pinMode(stop_pin[piez_idx], OUTPUT);
pinMode(kick_pin[piez_idx], OUTPUT);
#ifdef SHOW
cnt++;
velocity = kick_val[piez_idx];
Serial.print("IDX="); Serial.print(chan);
Serial.print(" Vel="); Serial.print(velocity);
Serial.print(" cnt="); Serial.println(note);
}
}
if ( kick_val[piez_idx] < adc ) {
kick_val[piez_idx] = adc;
}
if ( micros() > tm[piez_idx] ) {
tm[piez_idx] = 0;
mute[piez_idx] = true;
#ifdef ANOTHER_MUTE_PIN
pinMode(stop_pin[piez_idx], INPUT);
pinMode(kick_pin[piez_idx], INPUT);
}
}
}
Download Arduino Code
Click Here
Circuit Diagram
*******************Six pad Octapad***************************
********************Eight pad Octapad*******************************
Piezo Sensor Diagram
Upload the Arduino Code ,Arduino UNO Board using Arduino Cable.
And open the LoopMIDI and Hairless MIDI Serial softwears.
Open the FL Studio softwear and go to Option setting and go to MIDI section and Enable MIDI setting.
Open the code file in arduino IDE and go to Tools box and select the Arduino UNO board.
Open the FL Studio softwear and go to OPTIONS and
This project breakdown is a fantastic read for anyone interested in custom MIDI gear. Using piezo sensors to trigger percussion notes via analog inputs is such a clever, budget-friendly way to build a functional drum pad. Dealing with signal noise and threshold calibration during physical testing can get pretty tricky, so having access to Expert Arduino Assignment Help for Students is always a massive plus when troubleshooting sensor debouncing or latency in microcontroller sketches. Mapping dynamic pressure levels to smooth MIDI velocity values takes a fair bit of fine-tuning as well. Did you end up adding any serial-to-MIDI software bridges on the computer side, or did you flash the USB chip directly for native MIDI output?